Smoke eliminating apparatus



Aug. 11, 1936. J. GARVIE 2,050,653

I SMOKE ELIMINATING APPARATUS Filed March 23, 1933 ZShets-Sheet l JnvenZo'rr famed "we. )2

Aug.-ll, 1936. J. GARVIE 2,050,653

SMOKE ELIMINATING APPARATUS Filed March 23, 1933 I 2 Sheets-Sheet 2 50mm io/rt ya/mm 6 (Mr/166a Patented Aug. 11, 1936 UNITED STATES PATENT GFHQE SMOKE ELIMINATING APPARATUS James Gal-vie, London, England, assignor to British Smoke Eliminator Limited, London,

England 2 Claims. (01. 110-61) The present invention has for its object to improve combustion and/or to eliminate smoke in boilers of the locomotive type or other like boilers in which smoke tubes pass through the boiler,

for example in which a smoke box at one end of the boiler is connected by tubes to the combustion space'at the other end of the boiler. Another object of my invention is to enable improved combustion and smoke elimination't'o be effected by making use to some extent of the available features of construction of locomotive and like smoke tube boilers. It is'a well known fact that the rate of, distillation of the hydrocarbons is such that they cannot be consumed in the furnace of firebox of locomotive type boilers, the effect being that the partly consumed gases enter the smoke tubes as slow burning flames and are immediately extinguished and form smoke or solid carbon. This condition arises from the lack of suflicient air to complete combustion. A further object of this invention is to overcome these conditions in l the most efficient manner without necessarily having to effect material structural alterations in the existing boilers. The present invention is characterized by employing a number of adapter tubes, a substantially horizontal limb at one end of each adapter tube and means at such end whereby it can be readily fitted in the furnace end of a lower smoke tube of a locomotive boiler, each said adapter tube being formed with a substantially vertical part so as to extend downwards in continuity with the said smoke tube nozzles at the lower ends of the said adapter tubes directed in the opposite direction to the ends adapted to be fitted to a smoke tube, the said nozzles being adapted to direct steam preheated in the smoke tubes from the selected smoke tubes across the space between the combustion zone and the said firebrick arch in a direction away from the smoke tubes.

The said smoke tubes are utilized as pre-heaters for pre-heating the air conveyed to the combustion space, the said air being delivered in a Fig. 2 is a detail of the air tubes connecting the front header and the locomotive fire tubes.

Fig. 3 is a vertical sectional detail of an air emission nozzle directed into the furnace into the combustion zone, and themanner of adapting 5. same to a fire tube.

Fig. 4 is a broken vertical section of the preferred form of construction of the air supply tubes and jets as applied to a locomotive boiler with a firebrick bafile beneath the tubes. 10

Fig. 5 is a rear elevationof an assembly of air emission nozzles constructed as shown in Fig. 4.

Fig. 6 is a detail vertical section of aVenturi type of steam jet for obtaining the desired air pressure. 15

Referring to the drawings inclusive of the drawings, the invention is shown applied to the conventional form of locomotive boiler, the smoke box, smoke tubes and furnace of. which are indicated respectively by the reference numerals I, 2 20 and 3. The examples of the invention shown make use of a number of the lower smoke tubes as air conduits, a suitable but not essential number' of tubes for this purpose being six'preferably selected in a common horizontal plane for convenience of assembly and arrangement of steam ejectors 4 which can be arranged ina straight line mounted on the end plate 5 of the smoke box.

One of these steam jets employed is shown in Fig. 4, the steam inlet pipe 6 being connected to any avilable source of supply, preferably of dry steam. The flared or emission end M of the Venturi tube receives one end of an air tube I6 the otherv end of which is fitted into the appropriate smoke tube 2. These air tubes l6 can be sp'igoted, threaded, Welded or otherwise fitted into the smoke tubes. The air tubes Hi can be split linearly as at ll at their free ends and wedged into the smoke tubes, it being preferred to have the smoke tubes heated and the air tubes cold during the fitting operation, to obviate looseness.

The scoop l8 in the embodiment shown in Fig. 4 is a short tubular member open at both ends and directed forwardly so that with a travelling locomotive engine air can be drawn into the air tubes I 6 with or Without the assistance of the steam in the pipes 6, which can be fitted with individual or a common control cock for regulating and cutting off the supply of steam. It is preferred to shape the scoop l8 so that it has an inwardly downwardly diagonalled free edge as this obtains the most efficient scooping action.

In the arrangement shown in Fig. 1, instead of the scoops l8 being directed through the front of the smoke box and individually connected to their own air tubes l5 they are formed on the outer ends of a manifold 21 extending across the interior of the smoke box and formed with a central header 28 (see Fig. 2) into which are fitted the front ends of the air tubes Hi.

The air injected into the tubes I6 is carried through the appropriate smoke tubes and is thereby preheated and is ejected through nozzles 29 into the zone immediately above the combustion space of the furnace 3. The nozzles 29 are of high class heat resisting metal and for the usual form of locomotive boiler are as shown in Figs. 1 and 3 of substantially L configuration, with upwardly directed limbs carried through a furnace baflle or refractory wall 30, asbestos packing 3| being fitted about the nozzles. The upper ends of the nozzles are removably fitted in the outer ends of short air emission tubes 32 having split ends 33 similar to the tubes 5 by means of which they are fitted into the appropriate smoke tubes 2. The outer ends of these air tubes 32 are bent downwardly to receive the upper ends of the nozzles 29, and set screws 34 clamp the nozzles in the air tubes and enable the nozzles to be readily removed for repair and replacement.

The columns of air directed into the furnace so that they intersect are preferably delivered at the outlet end of the nozzles 29 over suitable deflectors, for example inclined vanes inside the nozzles so that the air entering the furnace has turbulence which results in the gases dispelled from the coal being burned.

In my present invention, the means for assisting consumption of the volatile gases or carbon content of the smoke emitted from the fire is intended to be readily adaptable to existing boilers of the locomotive type. For this purpose as shown in Fig. 4 two tubular elements are provided for each of the smoke tubes selected for conveying air and/or steam to the furnace, one tubular element l6a for the front or smoke box end of the boiler tubes and one 32a for the furnace end. The tubular element appropriate to the front end of the boiler connects the appropriate smoke tube 2 to a combined air and steam injector 4 and the tubular element appropriate to the furnace end is adjustable in length and direction of emission and in common with the front tubular element is shaped for adaptation to a smoke tube.

It is preferred as shown to employ four or more of the existing smoke tubes for the purpose of conveying preheated air to the furnace and to select them from near the base of the boiler and also to stagger them so that the tubular elements are in different planes within the smoke box by which means they are exposed to greater influence from the gases and steam escaping to the usual smoke stack. A convenient arrangement consists in shaping each tube as two horizontal end parts I62) and lBc joined by an integral downwardly inclined median part led, the lower and front ends being engaged in sockets formed in the inner ends of the steam ejector housings 4 fitted in the base of the door frame 5 of the smoke box.

With regard to the tubular elements 320. at the rear end of the boiler, i. e. those which project into the furnace space these can take the form of curved elbow tubes 321) as shown in Fig. 4 so that they eject the air nd/or steam substantially longitudinally relatively to the axes of the smoke tubes and by twisting these elbow tubes about the axes of the smoke tubes, in which they are fitted the ejected steam and air converges and sets up turbulence in the zone where the products of combustion are about to reach the rear ends of the tubes. By providing this turbulence at the lower part of the boiler end plate the products of combustion will have to pass upwards through the zone of turbulence with the result that the smoke will be supplemented with the preheated air and/or steam and its hydrocarbon content will be burnt. Such an arrangement is particularly suitable for use with a locomotive boiler of the type in which there is no firebrick baffle disposed in a plane across the furnace space above the firebars and below the boiler tubes, for example in many well known forms of shunting locomotives.

When the invention is to be applied to locomotive boilers of the type fitted with the aforementioned fire brick baffle as shown in Fig. 4, each tubular element 32a adapted to project into the furnace consists of a tube 320 adapted to pass vertically through the firebrick bafiie and formed with an elbow 32d at its upper end extending into a horizontal portion 32c, which may be split longitudinally, for insertion in the appropriate smoke tube. Slidable into the vertical part of this tubular element is an inner tube 32f projecting slight ly beneath the lower end of the vertical tube to receive an elbow shaped nozzle 32g the emission end of which extends horizontally or as shown at a small upwardly inclined angle to distribute the preheated air and/or steam across the plane close to the fire. The said inner tube 32; is held in position by set screws 32h and is axially adjustable so that the nozzle can be adjusted up and down and the said nozzle is adjustable about the axis of such inner tube in order to vary the angle of the axis of emission of the nozzles relatively to the longitudinal direction of the boiler. The vertical tubes are located close to the firebox tube plate and short elbow nozzles are employed so that by this means the preheated air is swept across the zone immediately adjacent the plane of the fire and by suitably adjusting the said nozzles, the ejected preheated air from the various nozzles converges and sets up turbulence in a zone which by said adjustment of the nozzles can be selected to produce the most eflflcient results as regards consuming the hydrocarbon content of the smoke. In this respect it will be understood that although the tubular elements at the smoke box end may be staggered as previously described the emission nozzles in the fire box can be adjusted to a common horizontal plane or staggered as required.

Suitable dampers or throttles can be provided in the air intake mouths or scoops for regulating the supply of air.

By means of the present invention the present dirt and inconvenience arising out of free discharge of smoke from locomotive stacks or funnels is eliminated by a simple and practical method involving little structural alterations to the boiler.

What I claim is:-

1. In smoke eliminating apparatus for boilers of the type with substantially longitudinal smoke tubes extending from a smoke box to a 7 vertical part being carried through the furnace firebrick arch so as to provide a part protected by the said arch extending downwards in continuity with the said smoke tube, nozzles at the lower substantially horizontal ends of the said adapter tubes located near the junction of the said firebrick arch and the fire box tube plate so as to direct steam preheated in the smoke tubes from the selected smoke tubes across the space between the fire bars and the said fire brick arch in a direction away from the smoke tubes, and means at the smoke box end for ejecting steam into the smoke tubes fitted with said adapter tubes, said substantially horizontal upper ends of said adapter tubes being split where they are fitted into the selected smoke tubes.

2. For use in smoke eliminating apparatus for locomotive boilers of the type with substantially longitudinal smoke tubes extending from a smoke box to a. furnace, a number of adapter tubes each of substantially Z outline, a split along one end of each of said adapter tubes to enable such end to be inserted directly into the furnace end of a smoke tube, the other end or the adapter tube constituting a nozzle for directing steam preheated in the smoke tube, to which the split end is fitted, across the combustion zone, and means for delivering steam from the boiler into the smoke box ends of the smoke tubes fitted with said adapter tubes.

JAMES GARVIE. 

